Blue wool-dye.



UNITED STATES PATENT OFFICE. I

CARL HEIDENREICH, 0F LEVERKUSEN, NEAR COLOGNE, GERMANY, ASSIG-NOR TO FARBENFABRIKE'N VORM. FRIEDR. BAYER & 00., OF ELBERFELD, GERMANY, A

CORPORATION OF GERMANY.

No Drawing.

Specification of Letters Iatent.

Application filed September 12, 1911.

Patented May '7, 1912.

Serial No. 648,996.

To all whom it may concern:

Be it known that I, CARL HEIDENREICH, doctor of philosophy, chemist, citizen of the German Empire, residing at Leverkusen, near Cologne, Germany, have invented new and useful Improvements in Blue Wool- Dye, of which the following is a specification.

My invention relates to the manufacture and production of 'a new and valuable azo dye having the formula:

It can be obtained by combining the diazo compound of 4-methyl-2-aminophenol-6-sul-' fonic acid with beta-naphthol.

My new dye is after being dried and pulverized in the shape of its sodium salt a violet powder soluble in water with a blue coloration. Blue fast shades on wool are obtained by dyeing my new azo dye according to the one bath process in the presence of a chrome mordant.

In order to illustrate the new process more fully the following example is given, the

parts being by weight:20.3 parts of 4- methyl-2-aminophenol-6-sulfonic acid are dissolved in 200 parts of water and 12 parts er cent. The solution is cooled to 10 a'cidulated with hydrochloric acid (1.19 spec. gravity) and diazotized with 6.9 parts of sodium nitrite. The yellow diazo solution is then added to a solution prepared from 14.5 parts of betanaphthol in 200 parts of water, 12 parts of caustic soda lye (30 per cent.) and 280 parts of a 10 per cent. soda solution. The mixture is stirred and heated during 45 hours to 4050 C. The dye is filtered off, pressed and dried. It yields upon reduction with stannous chlorid and hydrochloric acid 4 methyl-2aminophenol-G-sulfonic acid and l-amino-Q-naphthol.

Prepare the dye-bath with 4 per cent. of the dye: l-methyl-Q-aminophenoLG-sulfonic acid-l-beta-naphthol, bring to the boil, add 2 per cent. of potassium bichromate, enter the wool at 6080 0., bring to the boil, boil for 2 hour and add slowly 2-3 per cent. of acetic acid and continue boiling for 11% hours. A deep dark bluefast shade is thus obtained.

I claim p The herein described new azo dye having the formula:

' tion; yielding upon reduction with stannous chlorid and hydrochloric acid 4-methyl-2- aminophenol-o-sulfonic acid and 1-amino-2- naphthol; and dyeing wool in the presence of a chrome mordant according to the onebath method fast blue shades, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

CARL HEIDENBEICH. [L.S.]

Witnesses:

L. NUFER, ALBERT F. NUFER. 

